Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Available-for-sale securities, amortized costs	$ 326,634	$ 283,257
Available-for-sale securities, gross unrealized gain	10,664	4,281
Available-for-sale securities, gross unrealized loss	(266)	(588)
Debt Securities, Available-for-sale	337,032	286,950
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized costs	30,942	38,291
Available-for-sale securities, gross unrealized gain	879	469
Available-for-sale securities, gross unrealized loss	(10)	(27)
Debt Securities, Available-for-sale	31,811	38,733
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized costs	87,628	40,702
Available-for-sale securities, gross unrealized gain	4,281	1,422
Available-for-sale securities, gross unrealized loss	(46)	(26)
Debt Securities, Available-for-sale	91,863	42,098
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized costs	161,345	179,114
Available-for-sale securities, gross unrealized gain	4,512	2,163
Available-for-sale securities, gross unrealized loss	(165)	(442)
Debt Securities, Available-for-sale	165,692	180,835
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized costs	18,920	19,126
Available-for-sale securities, gross unrealized gain	665	221
Available-for-sale securities, gross unrealized loss	(8)	(40)
Debt Securities, Available-for-sale	19,577	19,307
Corporate Debt Securities [Member]
Available-for-sale securities, amortized costs		3,005
Available-for-sale securities, gross unrealized gain		6
Available-for-sale securities, gross unrealized loss		(45)
Debt Securities, Available-for-sale		2,966
Asset-backed Securities [Member]
Available-for-sale securities, amortized costs	27,799	3,019
Available-for-sale securities, gross unrealized gain	327	0
Available-for-sale securities, gross unrealized loss	(37)	(8)
Debt Securities, Available-for-sale	$ 28,089	$ 3,011

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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